Electrochemical process for cleaning and polishing silver plate and the like.



UNITED STAIEEBaTENT orrion.

ANTHONY MAURICE KOIILER, OF BRIXTON, LONDON, ENGLAND.

ELECTROCHEMICAL PROCESS F0 CLEANING AND POLISHING SILVER PLATE AND THE LIKE.

No Drawing.

Specification of Letters Patent.

Patented Feb. 7, 1911.

Application filed July 6, 1909. Serial No. 596,166.

by silver plate and the like may be cleaned and polished by immersing the article under treatment in an alkaline solution in the pres ence of aluminium or any alloy containing it in any proportion.

According to the present invention this cleaning and polishing solution may be made by dissolving any alkali or mixture of alkali s in water, and any suitable salt, powder or dye in any form may be added to the solution to give it color or increase its chemical action. The solution may be used hot or cold at any suitable temperature, and it may be contained in a vessel of any suitable shape,

' made of silver, china, silver plate or any suit-able material. The aluminium or the alloy cmitaimng it may be partly or fully immersed in the solution and it may be in any suitable form or shape and in any quantity.

, The chemical action taking place in acchrdance with the process forming the subject of my invention, when soda and alu- V minium are used, is as follows but use can be made of any alkaline solution or any aluminum alloy.

l/Vhen the article or articles are inmtersed in the solution and touch or are otherwise connected with the aluminium or alloy thereof employed, a chemical action takes place, causing hytilrogen to be liberated by decomposition, and this combining with the metallic oXid that really forms the tarnish on the surface of the article to be polished, thus forms water, leaving the surface as bright as itoriginally was before it was oxidized or tarnished. The separation of the hydrogen from the alkaline liquid causes a certain amount. of the alm'ninium hydroxid or alloy thereof to be dissolved, which again forms aluminium hydroxid Al((.)l'-I),,, in addition to the respective hydroxids (it an alloy is employed, and depending on the kind of alloy) which would in some cases be reduced to r\l(( )1 due to the prcscnce of aluminium, or otherwise accomplish the ame result as the aluminum hydroxid, i. in producing various sets of compounds or salts according to the composition of, the al- 10' when such is employed, thus forming a slight white film upon the surface of the article to be polished which may be removed by rubbing and leave said surface perfectly bright and clean.

'Although I have mentioned NaOII as'a preferable alkaline solution, I may (in some cases use a solution of the salts of other alkaline metals, and the percentage of alkali in the solution depends on the quantity and quality of the articles to be cleaned and polished, and the proportions would therefore var and in the"employment of an alloy of aluminium the percentage of aluminium in such alloy would also depend on the quantity and quality of the articles to be cleaned and polished, and these proportions would also vary.

An example of an alloy to be used in place of aluminium is as follows:

Aluminium parts. Barium 10 parts. Calcium 8 parts. Sodium 1 part. Silicium and other in'ipurit-ics 1 part.

100 parts.

This alloy may be partly or fully immersed 1n the solution and 1t may be in any suitable form or shape and in any quantity,

When such an alloy as above is employed Said salt or compound may take .part in the polishing process straightwa y, or in some cases is decomposed, producing commands such as aluminum 'hydroxid, depending on the alloy or alkaline solution used.

Other of the alloy constituents such as sodium may form their respective hydroxid straight-Way, thus If the articlesto be cleaned are greasy or very much soiled, they may be immersed in a heated solution of NaCO before placing in the solution for polishing hereinbefore described. t

Having now described my invention, what I claim as new and desire to secure by Letters Patent of the United States is f A process of cleaning and polishing plated articles and the like, which consists in im- 15 mersingin a receptacle containing an aluminium salt solution, aluminium and the article to be cleaned, hydrogen thereby being liberated and combined with the oxi'd on the article to produce Watenand afterward dryring the article.

In testimony whereof I have aflixed my signature 1n presence of two Wlt-IRZSSGS.

ANTHONY MAURICE Korma.

Witnesses:

BENJn. Tnos. KING, Rom. HUNTER. 

